K1 Technologies connecting rods are quality built from billet 4340 steel for superior strength in high horsepower applications. K1 has also called upon the experts at ARP fasteners to design special K1 proprietary rod bolts with asymmetrical threads to equally load each thread when under pressure. K1 rods are shot peened for improved fatigue life and are finished in the USA using only state of the art Sunnen hones. K1 rod housing bore tolerances of +/- .000050in (50 millionths) match some of the tightest accepted tolerances in the industry. All K1 rod sets are weight-matched to +/- 1 gram and boxed with the individual rotating, reciprocating, and total weights conveniently noted for balancing. A special wrist pin bushing material is also used with these assemblies offering optimal friction reduction. Note: K1 Rods are sold in full sets or four (4) rods.